<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    .cont1{
      width: 200px;
      height: 200px;
      background-color: pink;
    }
    .cont2{
      width: 100px;
      height: 100px;
      background-color: rgb(145, 180, 255);
    }
  </style>
</head>
<body>
  <div class="moveDom">
    <div class="cont1">
      <p>内容区1</p>
    </div>
    <div class="cont2">
      <div>div-其他标签</div>
      <p>内容区2</p>
      <p>要移动的内容</p>
    </div>
  </div>

  <script src="http://www.jq22.com/jquery/jquery-1.10.2.js"></script>
  <script>
    // 把要移动的元素添加到目标节点中
    $(".cont1").append($(".cont2 p:nth-child(3)"))
    // $(".cont1").append($(".cont2 p:nth-of-type(2)"))

    
    // $(".cont1").css('backgroundColor','red')
  </script>
</body>
</html>